The invention relates to a mechanism comprising an induction tube of an internal combustion engine and in which is disposed a pivotal air flow meter and an operator controlled throttle valve. The air flow meter is moved against a restoring force in accordance with the quantity throughflow and the movable component of a valve disposed in the fuel line for apportionment of a fuel quantity proportional to the given air quantity is accordingly displaced. The presently known devices are incapable of current requirements of mass production and assembly line installation. This invention is intended to fill the void in the prior art.